I just purchased a wardrobe staple for the first time in years. The penny loafer, or Weejun style shoe. I stayed away from Bass and upped the ante to a pair from Geox, as I like the idea of breathability in a loafer that may sometimes be worn sockless. I guess what I'm asking here is... how formal would you go with these, and at the same time, how informal? I know that a sportcoat and chinos would fare well, but for a shoe that's supposed to be so versatile, how much versatility can I muster?